Pelagius, the founder of the religious system called Pelagianism. Little is known of his life, but he is supposed to have been a British monk whose real name was Morgan. He went to Rome about 409, where he was distinguished by his purity of life and his zeal for the reform of the clergy and laity. With his disciple Ooelestius he went to Carthage in 411. Pelagius soon left Africa for Palestine, but Ooelestius, who endeavored to be admitted among the presbyters of Carthage, was accused of heresy before a synod held in that city in 412 and condemned for the following doctrines: 1, Adam was created mortal, so that he would have died whether he had sinned or not; 2, Adam's sin injured only himself, and not the human race; 3, new-born infants are in the same condition in which Adam was before his fall; 4, the whole human race neither dies in consequence of Adam's death or transgression, nor rises from the dead in consequence of Christ's resurrection; 5, infants obtain eternal life, though they be not baptized; 6, the law is as good a means of salvation as the gospel; 7, there were some men, even before the appearance of Christ, who did not commit sin.
These seven propositions (others count only six, leaving out the fifth, or joining it to one of the other propositions) are still regarded as the cardinal points of the Pelagian system, although it is difficult to decide how far Pelagius accorded with all of them. In consequence of the condemnation of Coelestius, Pelagius himself was soon attacked in Palestine, where Jerome became one of his most zealous opponents. Jerome, conjointly with Orosius, accused Pelagius at a synod held in Jerusalem in 415. The matter was referred to Pope Innocent I., but at another synod of 15 bishops, held in the same year at Diospolis, under Eulogius of Caesarea, Pelagius was acquitted. The churches of Africa reiterated their rejection of the system in a synod of 69 bishops at Carthage, and in a synod of 61 Numid-ian bishops at Mileum, both held in 416. The decision of Innocent was satisfactory to the African bishops, and Pelagius addressed to him an explanatory statement, which did not reach Rome until after Innocent's death. His successor, Zosimus, was induced by the confession of faith that Ooelestius, then in Rome, had drawn up, and also by the letters and protestations of Pelagius, to declare the two accused sound in faith and unjustly persecuted.
The African bishops, 214 in number, met again in a synod at Carthage, and stood by their former decision; and Augustine, the most powerful opponent of Pelagius, appealed to the emperor Honorius (418), who ordered the suppression of the new heresy. Another council at Carthage, attended by delegates from all the provinces of Africa, specified and solemnly condemned as heretical nine doctrines of Pelagius. Similar declarations were issued by the bishops Theodotus of Antioch and Praylius of Jerusalem. Zosimus now also lost confidence in the new teachers, and published his Epistola Trac-toria, in which the Pelagian doctrine is condemned. Many bishops of the western churches subscribed to this epistle; but Julian, bishop of Eclanum in Apulia, undertook the defence of the system. He had to sacrifice his office, and to go with Pelagius and Ccelestius to Asia. Little is known of the further history of Pelagius, his two friends, and their doctrines, except that the last were again condemned as heretical by the oecumenical council of Ephe-sus in 431. The followers of Pelagius never formed a sect properly so called, but Pela-gianism long maintained a foothold in the church. - See "Wiggers, Versuch einer prag-matischen Darstellung des Augustiniantsmus und Pelagianismus (2 vols., Berlin, 1831-'3; English translation by Prof. Emerson, New York, 1840), and Jacobi, Die Lehre des Pelagius (Leipsic, 1842).